Abrasive disk



June 23, 1931. F. o. ALBERTSON ETAL 1,311,037

' ABRASIVE DISK Filed Dec. 50, 1927 2 Sheets-Sheet 1 June 931. F. o. ALBERTSON ETAL 1,811,037

ABRASIVE DISK Filed Dec. 30. 1927 2 Sheets-Sheet '2 Patented June 23, 1931 UNITED STATES PATENT OFFICE IRANS O. ALIBEBTSON AND GUSTAV OLSEN, 0F SIOUX CITY, IOWA, ASSIGNORS TO ALBEBTSON & COMPANY, INC., OF SIOUX CITY, IOWA, A CORPORATION OF IOWA ABRASIVE DISK Application filed December 30, 1927. Serial No. 243,492.

The present invention relates to abrasive disks and is more particularly concerned with abrasive disks adapted to be used for sanding or smoothing automobile bodies.

One of the objects of the present invention is the provision of a simplified abrasive disk structure capable of accomplishing better results than the complicated abrasive disk structures of the prior art, and, at the same time, eliminating many of the elements heretofore considered essential in a resilient and flexible abrasive disk.

Another object of the invention is the provision of a more economical, yet durable, abrasive disk structure having quickly detachable securing means for carrying the abrasive sheet, which securing means is adapted for repeated use and for securing abrasive sheets in various usefulpositions.

Anotherobject of the invention is the provision of a simplified resilient and flexible abrasive disk support comprising a minimum of structural elements which may be manufactured more cheaply than the structures of the prior art but which is capable of performing all of the functions of such a disk in a more efiicient manner and for a longer period of time. I

Other objects and advantages of our invention will appear more full from the following description and from t e accompanyin drawings, in which similar characters of re erence indicate similar parts throughout the several views.

In the drawings, 4

Fig. 1 is a plan view of the face of our abrasive device;

I Fi 2 is a cross sectional view taken on the line 22 of Fig. 1; Fig.) 3 is a lan view of the rear face of our a rasive evice in combination with an abrasive sheet of the same size;

Fi .,4 is a cross sectional view taken on the line 4-4 of Fig. 3; and

Fig. 5 is a view in perspective of the sheet metal securing member reduced in size.

In the embodiment which we have chosen to illustrate our invention, 10- indicates, in its entiret the supporting disk of our abrasive evice, 11 the abrasive sheet or sheets carried thereby, and 12 the quickly detachable securing means.

Thesupporting disk 10 may consist solely of a hub 13 fixedly secured to a resilient and flexible metal disk 14, preferably formed of relafively thin tempered steel, that is, spring stee The metal disk 14 may be secured to the hub 13 by forming said hub with a central bore 15, a shoulder 16 and a reduced portion 17 adapted to be rece'ved in an aperture 18 in the metal disk. he reduced portion 17 and aperture 18 are made circular in form for convenience in machining but may obviously be made of any other shape desired.

The outer end of the bore 15 isswedged outward over the edge of the metal disk 14 about the aperture 18, thereby riveting the metal disk upon the hub 13. i

In order to provide additional support for the metal disk upon the hub, the hub 13 is provided with an integral, radially projecting flange 19 and the metal disk 14 is riveted to said flange at a plurality of points by rivets 20 passing through the flange and metal disk.

The rivets 20 and swedged portion 21 of the hub are, of course, machined to a smooth surface on the face of the metal disk, and, if desired, both the-"rivet holes and aperture 18 may be slightly countersunk.

The hub 13 is provided with threads 22 in the bore 15 for engagement with a threaded supporting arbor and the hub may be provided with an enlarged portion23 for engagement with a wrench or other tool when necessary to remove the device from the arbor. The provision of the enlarged bore 24 adapts the device for use with an arbor having a reduced threaded end and a shoulder to engage the annular shoulder 25 in the hub, to limit the threading movement of the hub upon the arbor.

In order to provide means for securing an abrasive sheet upon the metal disk 14, themo v ing disks, the flange 19 may be cutaway adrality of ears 28 upon a sheet metal securing ing sheet. This is the member 12, the ears 28 being located to pass through similarly located slots 29 in the abrasive sheet and the slots 26 in the supporting disk and being bent over on the rear face, as at 30, to bind the abrasive sheet upon the supporting disk. I

The securing plate 12 may be formed of a sheet of relatively heavy tin having a plurality of tabs or ears 28 punched out of the same at points located to register with the slots 26. As the force exerted u on the abrasive disk is a rotative force, t e slots and ears 28 preferably extend radially, providing an increased bearing surface between the ears 28 and the edges of the slots 29 in the abrasive sheet.

The abrasive sheets 11 are preferably formed of circular pieces of emery paper, emery cloth or sand paper, and, if the base upon which the abrasive is carried is of sufficient rigidity, no backing sheet is required. However, with the ordinary commercial emery cloth, we prefer to cement this abrasive upon a relatively thin backing sheet of fibreboard, the fibre-board 30 being provided with the slots 29 to receive the ears 28.

We desire it tobe understoodsthat our invention includes the use of the foregoing structure, with or without pads upon the resilient metal disk, but in the preferred form our disk support 1s also provided with a felt pad 31 of slightly larger size than the metal disk 14, having slots 32 registering with the slots 26 and- 29. The felt pad 31 may be secured to the resilient metal disk by a plurality of rivets 33 passing through the pad and metal disk and upset in such manner that their heads 34 are countersunk in the pad 31 and swelled in the rivet holes 35.

7 In the embodiment shown in Fig. 4, the

securing plate 12 is fixedly secured to the abrasive sheet 11 between the backing sheet 30 and the emery cloth 36,' the tabs 28 pro jecting backward through slots in the backo'rm preferably employed Where a smallTthree-inch sanding disk is to be-used, thereby utilizing the whole surface of this small abrasive disk.

In the form shown in Fi 1 and 2, the securing. plate 12 is loose an separable from both the supporting device 14 and the abrasive sheet 11. In this embodiment, the central portion 37 of the emer cloth may be removed since it would or inarily be covered by the securing plate and only the outer ortion 38 of the emery cloth is intended to used.

It will thus be observed that, with the embodiment shown in Fig. 1, the emery cloth or other abrasive may be made to face toward the rear of the abrasive device or toward the front of the same, or two abrasive sheets may be employed, as shown in Fig.2, providing an extremely useful device.

With the combination shown in Fig. 2, the operator may very conveniently sand or smooth relatively inaccessible parts of automobile fenders or other points where onl the back 38 of the abrasive can be inserte At the same time the frontsheet is available for the usual operations and both sheets may be inserted into cracks or between parts of the body where ordinary abrasive devices could not be used. 4

The abrasive disk'support, shown in Figs. 3 and 4, is substantially the sameas that shown in Figs. 1 and 2, illustrating the use of the support with an abrasive sheet of substantially the same size as the metal disk and pad. In this embodiment (Fig. 4) the resilient metal disk 14 has been made substantially larger than that shown in Fig. 2, the tempered metal disk being adapted to flex upon engagement of the abrasive with an article. Thus the abrasive surface is su ciently yielding to conform itself to the curvature of the article to be smoothed and the device may be operated without removing too much material from any point to produce an even smoothing action.

The spring steel disk is adapted to be used for long periods of time, retaining its resilient qualities better than rubber or the like. At the same time, our abrasive disk support is easy to manufacture and assemble, having a minimum of parts which greatly reduces the cost of its manufacture.

The securing plate 12 may be used many times with new sheets of abrasive where the securing plate is separable as shown in Fig. 1.

While we have illustrated and described a specific embodiment of our invention, many modifications may be madewithout departing from the spirit of the invention, and we do not wish to be limited tothe precise details of construction set forth, but desire to avail ourselves of all changes within the scope of the appended claim.

Having thus described our invention, what we claim as new and desire to secure by Let- I ing of fiber board, said abrasive disk, pad

and metal disk having a plurality of apertures and a separate metal plate located outside said abrasive disk and having a plurality of bendable tabs for passage through said apertures in said pad and metal disk to secure said abrasive disk on said abrasive device in either of two ositions.

In witness whereo we hereunto subscribe our names this 12 day of December, 1927.

FRANS O. ALBERTSON; GUSTAV OLSEN. 

